#include <iostream>
#include <string>

int main()
{
	std::string str = "";

	std::cout << "Enter string: ";
	std::getline(std::cin, str);

	int n = 0;

	for(int i = 0; i < str.length(); ++i)
		if('0' == str[i] || '1' == str[i])
    {
			++n;
    }   
	if(n == str.length())
	 {
    std::cout << str << " is binary number\n\n";
	}
  else
  {
		std::cout << str << " isn't binary number\n\n";
  }
	return 0;
}